Electric cigarette lighter



L. K. DAVIS ELECTRIC CIGARETTE LIGHTER Oct. 8, 1957 3 Sheets-Sheet 1Filed April 6. 1953 INVENTOR [inc-ah Kfiavzls,

BYMfM ATTORNEYS Oct. 8, 1957 K. DAVIS ELECTRIC CIGARETTE LIGHTER 3SheetsSheet 2 Filed April 6. 1953 INVENTOR A lineal/z fli'flavw;

ATTORNEYS Oct. 8, 1957 DAVls 2,809,266

ELECTRIC CIGARETTE LIGHTER Filed April 6. 1953 3 Sheets-Sheet 3 wiwATTORNEYS harem: Ofilice assess-s Patented Oct. 8,

ELECTRHC CEGARETTE LIGHTER Lincoln K. Davis, Broclrton, ApplicationApril 6, 15753, Serial No. 347,016 3 Claims. (Cl. 219-32) This inventionrelates to improvements in electric cigarette lighters, such for exampleas are adapted to be mounted on the instrument panel of an automobilefor operation at the relatively low and often variable voltage availablefrom the storage battery of the automobile.

he invention is of that class in which ignition of a cigarette iseffected by an electrical resistor, rendered incandescent for thepurpose, and combustion is stimulated by forcing air through thecigarette, flow of air being efifected by expanding air within aconfined space by means of heat derived from an electrical resistoraided by the igniting resistor, the arrangement being such that thecigarette, while being ignited, forms the only exit from the air space.The air flow through the cigarette is thus effected without the use ofmechanical pumping means.

One prior art example of this class of lighter will be found in myPatent No. 1,983,738, granted December 11, 1934. The lighter of thispatent was intended primarily for table use in the home and the timerequired for lighting the cigarette was not a particularly importantfactor. Current in the two resistors was substantially constant and hadto be kept within low limits in order to prevent the resistors fromburning out in case the circuit was kept closed longer than necessaryfor ignition of the cigarette. The igniting resistor was relatively slowin becoming incandescent and the air flow had to be delayed until theigniting resistor was hot enough to function. The time'delay was securedby thermal inertia, the slowness in expanding the air in the air chamberwith the amount of heat applied. The volume of the air space wasrelatively small, providing outflow of air through the cigarette foronly a short interval of time.

For automobile use, time is of the essence and the lighting of thecigarette must be effected as quickly as possible, in two or threeseconds, and with a minimum of eiiort on the part of the operator so asto detract as little as possible from his attention to the work ofdriving the automobile. At the same time, provision must be made toprevent the igniting resistor from burning out, when the operator doesnot immediately withdraw the cigarette immediately after it is lightedand maintains the circuit closed longer than necessary.

This invention has for its general object the improvement of a cigarettelighter of the class described to provide faster ignition, longer flowof air through the cigarette and better timing of the air flow withrelation to the action of the igniting resistor.

More particularly, it is an object of this invention to provide in acigarette lighter of the class described an air-heating resistor whichhas a higher temperature coefficient of resistance and which isconnected in series circuit with the igniting resistor, the arrangementbeing such as to allow initially and for a brief interval current in thecircuit of a value that is higher than would be safe for prolongedoperation, whereby the igniter may be rendered incandescent almostinstantaneously and made to deliver for a brief interval much more heatthan would 2 otherwise be possible, whereby to heat the relatively largevolume of air that is necessary in order to secure air flow over therelatively long time interval desired and do so quickly enough so thatthe air flow through the cigarette will commence immediately followingignition of the latter.

These and other objects will more particularly appear from the followingdescription of the invention with reference to the accompanyingdrawings, in which,

Fig. l is a sectional elevational view of a cigarette lighter embodyingthe invention;

Fig. 2 is a cross sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a cross sectional view taken on the line 3-3 of Fig. 1;

Fig. 4 is a sectional elevational View of a second form of cigarettelighter embodying the invention;

Fig. 5 is an exterior front elevational view of the cigarette holdingcasing of the lighter;

Fig. 6 is a cross sectional view taken on the line 6-6 of Fig. 4;

Fig. 7 is a cross sectional view taken on the line 7-7 of Pig. 4;

Fig. 8 is a cross sectional view taken on the line 8-8 of Fig. 4;

Fig. 9 is a fragmentary sectional plan view taken on the line 9-9 ofFig. 4; and

Fig. 10 is a fragmentary cross sectional view taken on the line 10-10 ofFig. 4.

Referring to these drawings, the cigarette lighter in general utilizestwo electrical resistors, located within and adapted for heating the airwithin a confined space and by expansion of the air causing an outflowof air through a single passage, which forms the only outlet from suchspace. in this passage, the cigarette to be ignited is inserted so thatit closely fits the walls of the passage, thereby forcing the outflow ofair to pass through the cigarette, while the latter is ignited by one ofthe resistors, which becomes incandescent for that purpose. This airspace may be formed within a housing-means of any suitable form,composed of one or more chambered casing elements, the hollow interiorsof which are interconnected to form the air space.

in the example shown in Fig. 1, the air space 1 is formed within thecasing elements 2, 3 and 4, which enclose the space except for a singlepassage 5, which is of a size to receive and closely fit a cigarette,indicated by dotted lines at 6, the inner end of which lies adjacent tothe inner end of passage 5 and closely adjacent to a first electricalresistor 7. This resistor is suitably connected in series with a secondelectrical resistor 8 in an electrical circuit which includes a suitablecontrol switch, such as the elements 9 and 1%, and which is adapted tobe connected to a suitable source of electrical supply, such as thestorage battery, indicated diagrammatically at 11, of an automobile.

Referring next to the details of the exemplary apparatus shown in Fig.l, the described electrical circuit includes ground, battery 11, wire12, metal bolt 13, ballast resistor 8, metal post 14, metal leaf spring15, metal post 17, igniter resistor 7, metal post 16, switch blade lib,grounded switch element 9. It will be understood that switch element 9is integrai with the rod slidably mounted in,-and in electricalconnection with, the metallic grounded casing element 4, and adapted,when manually pressed inwardly, to engage the spring switch blade 10 andclose the described circuit. A spring 19 coiled around rod 1% and actingbetween casing element 4 and pushbutton 2i) aflixed, as by screwthreads, to rod 18, yieldably holds the switch elements 9 and 10disengaged when the circuit is open. The casing 2 is of non-conductingmaterial.

-limit of such range.

As to the particular housing-means shown, the casing element 2 is ofhollow cylindrical form, preferably of heat-insulating andelectrical-insulating material and having one integral end wall. Theelement 3 has a part 21 screw-threaded into the other end of cylinder 2and an interiorly threaded tubular part 22 receiving theexteriorly-threaded tubular part 23 of easing element 4. The part 23 isadapted to pass through a hole in the metallic instrument panel 2 of anautomobile until a shoulder 25 on the casing 4 abuts the outer face ofthe panel. The part 22 serves as a nut to clamp the shoulder 25 againstthe panel 24. The posts 16 and 17 are fixed to a cross bar 26 ofinsulating material, which is fixed at its ends by screws 27 (Fig. 2) tothe inner end face of tubular part 23. The post 14 is fixed to a crossbar 28, the ends of which are secured, as indicated, to the peripheralwall of casing element 2.

This invention is characterized in that the resistor 8 has a hightemperature coeflicient of resistance, whereby its resistance increaseswith its temperature from a relatively low value at the low limit of itsoperating range of temperature, to a relatively high value at the highThe increase in resistance which occurs during the temperature rise ofthe resistor 8 within these limts, is several hundred percent and, inthis particular example, about 550 percent. The resistor 7, on the otherhand, does not change materially with the rise in its temperaturethroughout its operating range, varying for example no more thanpercent. The effect of the arrangement described is to produce initiallya flow of current in the circuit which is of a value greater than wouldbe safe to use for more than a very short time. This high current, whichlasts but a moment, is checked by the increase in resistance of resistor8, as its temperature rises, until the current falls to a minimum valuewhich is safe for prolonged operation. For example, in the presentexample, the current is initially about 17 amperes and decreases inabout two seconds to 7.5 amperes. The result is the production quicklyof a high initial heat, whereby the igniting resistor 7 is instantlyrendered incandescent and very hot to quickly heat up the inner end of acigarette and ignite the same and also to quickly heat the air confinedin the air space 1. Both resistors serve to heat such air. As the air isheated, its pressure increases, until it becomes great enough to causeair flow through the cigarette. There is always a certain amount ofdelay in building up pressure in this manner because of thermal lag. Theextent of such delay will vary according to the volume of the air space,the mass of resistor S, and the amount of heat applied to heat the airin such space. By reducing the volume of the air space, the delay inproducing the outflow of air through the cigarette can be reduced forany given amount of heat applied. However, it is essential to haveenough volume of air space to secure outflow of air through thecigarette for a long enough time and also to supply suflicient oxygenfor combustion. Flow of air starts only when the air has been heatedenough to build up the pressure to the value necessary to force airthrough the cigarette and it continues only while the pressure is at orabove such value. Usually, a pressure, corresponding to 9 or 10 inchesof water, will sufiice for the purpose. After the air in the space hasbeen heated to the maximum degree possible, the air will flow throughthe cigarette only until the pressure in the air space has been reducedbelow such value. The time or air flow through the cigarette depends onthe volume of the air space and it is therefore necessary tomaintain acertain minimum volume. A volume of from 10 to cubic inches isconsidered adequate. The volume of the air space in the present'exampleis about half a pint.

The invention enables the use of the relatively large air space, whichis necessary to maintain outflow of air for the relatively long intervalnecessary, and offsets the increase in delay, due to thermal lag, by thelarge increase in heat obtained by the use of the resistor 8, whichallows for a short interval, a much higher heat than would be possibleto obtain with an ordinary resistor and the current available for thepurpose. The outflow of air is to timed that it starts only after thecurrent flow has decreased somewhat from its high initial value.Therefore, the resistor 7 will not be subjected to the cooling effect ofthe flow of air past it until it has had time to heat and ignite thecigarette. The temperature of the air, when it flows outwardly isconsiderably less than that of the temperature of resistor 7, when themaximum current passes through it, and hence there would be asubstantial heat exchange between resistor 7 and the air, which exchangewould result in lowering the temperature of resistor 7 from the highmaximum value desired for the short time. While the outflow of airshould not occur until after this high initial current flow, it shouldnot be delayed long and should commence before the current flow hasdecreased to its minimum value. The desired condition is to blow airthrough the cigarette as soon as it is ignited by the high initial heat.With the described arrangement, the air will flow through the cigarettein about one second after the switch 9, 10 is closed and the cigarettewill be fully lighted and ready to be withdrawn in about two seconds. Ifthe operator does not then withdraw the cigarette, the air flow willcontinue for five or six seconds and the igniting resistor 7 will bemaintained at its minimum safe temperature so that the cigarette will bekept lighted.

One illustrative example of values which have been found suitable forthe electrical elements of a six-volt cigarette lighter will be given.The resistor 7 is made of ordinary resistance wire and has a resistanceof .21 ohm, which increases with the rise in temperature that occurs,only about 9 percent. The resistor 8 is made of ordinary shim stock(soft steel), having a thickness of .002 inch, a width of .14 inch andan eifective length of 7% inches. The resistor 8 has a temperaturecoefiicient of resistance of .0016 percent per degree centigrade. Itsresistance will vary from a low value of .12 ohm to a high value of .66ohm during the temperature rise that normally occurs. The increase inresistance of resistor 8 is thus 550 percent. The volume of the airspace is approximately 15 cubic inches. With these values, the currentin the circuit is initially l7 amperes and decreases to 7.5 amperes in 2or 3 seconds. Initially, 102 watts is dissipated in heat for quicklyexpanding the air to the pressure necessary to start flow through thecigarette and is reduced more than one-half to 45 watts in the 2 to 3second interval. Outflow of air through the cigarette starts in aboutone second after closure of the switch and continues for 5 to 6 seconds.In about one second after the switch is closed, smoke will commence toissue from the cigarette and in another second or two the cigarette willbe fully lighted and may be withdrawn. On the other hand, if thecigarette is not then withdrawn, the current flow will be held to a safevalue to prevent the resistor 7 from burning out. The resistor 8,therefore, acts as a ballast for the igniting resistor 7.

In the embodiment of the invention shown in Figs. 4 to 10, the housingmeans (Fig. 4) includes separate chambered casing elements 30 and 31,the hollow interiors of which are interconnected by a conduit, includinga tube 32 fixed to the cap 33 of casing 30, a tube 34 fixed to the cap34 of casing 31 and a flexible hose 35 which interconnects these tubes.The air space comprises the space within the chambers 36 and 37 ofcasings 30 and 31 and the space 38 within the described conduit. Theonly exit from this air space is by way of a passage 39, in which thecigarette is adapted to be placed in closely-fitting engagement with thewalls of such passage. The igniting resistor 7 is located in the chamber36 near the inner end of passage 39 and the ballast resistor 8 islocated in the chamber 37. This chamber has about the same volume as theair space 1. As shown it is formed within a halfpint Mason jar, such asis used for canning preserves. The resistors are identical inconstruction, material and electrical values with the correspondingresistors shown in Fig. 1. These resistors, as before, are connected inseries in a circuit adapted to be supplied by a six-volt storage batteryof an automobile and controlled by a switch consisting of a rod 40,operable by a push button 41, and a contact 42. The operation of thelighter shown in Fig. 4 is identical with that shown in Fig. 1.

Referring next to the details of the exemplary apparatus shown in Fig.4; the casing 30 is metallic; has a cylindrical part 43 which passesthrough a hole in the instrument panel 44 of an automobile; and ashoulder 45 adapted to be drawn against the front face of such panel bymeans of a U-shaped clamp 46, through the cross bar portion of which thetube 32 passes and the legs of which abut the back face of panel 44, anda nut 47 threaded on tube 32. This cap, which is of insulating materialand fixed to casing 3% by two screws 43, as shown in Fig. 7, has fixedthereto two metal posts 49 (Fig. 9), which extend forwardly in cham ber36, one on each side of tube 32, and have fixed to their inner ends, asby screws 50, the ends of the resistor 7. The outlet of tube 32 (Fig. 4)is positioned beneath the igniting resistor 7 in order to direct airthrough it and through a cigarette when positioned as described in thepassage 3?. The switch contact 42 is located on the inner face of cap 33and is fixed thereto by a metal rivet 51, which extends through the capand has its outer end connected by a conducting strip 52 (Fig. 7) to theouter end of one of the posts 49. The switch rod 40, the inner end ofwhich is adapted to engage contact 42, is slidably mounted in themetallic casing 30 and thus electrically connected by the latter to themetal panel 44 which is grounded to the frame of the automobile. Thepush button 41, which is of insulating material and is fixed to theouter end of rod 4%, has fixed to its inner face a stud 53, whichprojects through an end wall of chamber 36 and has a head on its innerend adapted to engage such wall to limit the outward movement of thepush button under the force of a spring 54. The other post 49 (Fig. 7)has fixed thereto a clip 55, to which is connected one end of a wire 56(Fig. 6), the other end of which is clamped between two nuts 68,threaded on the outer end of a bolt 6% which clamps the metallic cap 34'of casing 31, as indicated in Fig. 4, between the insulating washers 66and 67 and clamps one end of resistor s between its head and washer 66.This casing 31 is preferably of heat-insulating andelectrical-insulating material. The tube 34, which has a head (at? onits lower end, passes upwardly through cap 34 and insulating washers 53and 5% arranged on opposite sides of the cap and is held in place by oneof a pair of nuts 57. Clamped between head 61) and washer 59 is theright-angularly bent upper end 61 of a metallic strip 62, which extendsdownwardly nearly to the bottom of chamber 37 and has fixed to its lowerend the other end of the resistor 3. This resistor is bent in spiralform and supported at locations intermediate its ends by insulators 63,mounted on arms 6 fixed to and projecting. outwardly from member 62.Clamped between the nuts 57 is one end of a wire 6, the other end ofwhich is adapted for connection to the ungrounded terminal of thestorage battery.

Each form of the invention includes the same essential elements, havingthe same values and characteristics and functioning in the same way. Thesecond described form of the invention may be more sui able, as apractical matter, for the modern automobile because of the use of acasing such, as 31, which provides within it most of the air spacenecessary and which may be located at a distance from the instrumentpanel where more space is available.

This second form of cigarette lighter is disclosed in a copendingapplication for patent, filed December 11, 1952,

6 by Glen A. Guernsey and Arthur H. Green, under Serial No. 325,366, nowPatent 2,73l,540. In this application are claimed certain featuresrelating to the air nozzle and the construction and mounting of thecasing 30.

The invention provides an electric cigarette lighter which is especiallyadapted for use in automobiles because it affords fast ignition withlittle efiort on the part of the operator. He simply positions acigarette in the receiving passage, such as 5 or 39, and presses abutton, such as 20 or 41, for two or three seconds and the cigarette islighted. The lighted condition of the cigarette will be manifested by asubstantial outflow of smoke from the outer end of the cigarette andthen the cigarette should be removed. However, if the cigarette is notimmediately removed and the switch button is kept pressed in, no harmwill be done because the current in the circuit will have been reducedby the increased resistance of resistor 8 to a value which is safe forprolonged operation. The flow of air is obtained solely by expansion ofair due to heat from electrical resistors and occurs automatically inproper timed relation with the ignition, eliminating the need formechanical pumping means and valves for controlling the timing.

The lighter provides the large volume of air space that is necessary toprovide, with the heat available, for the desired air flow through thecigarette for the relatively long time interval necessary. The use ofsuch a large volume of air would, if heated by ordinary resistors,result in increased delay in the commencement of the air flow because ofthermal lag. The special type of resistor used, because of itscharacteristics, provides initially for much higher current in thecircuit than could be used continuously, and therefore provides muchmore heat. This increased heat offsets the thermal delay and enables thedesired timing of air flow with relation to ignition. The ignitingresistor becomes incandescent instantaneously on closing of the circuitand quickly cooks the inner end of the cigarette, causing ignitionthereof, and the air flow to stimulate combustion follows almostimmediately after the momentary period of high current in the circuit.The cigarette will be thoroughly lighted in substantially the same timerequired to heat the igniting resistor of the apparatus or" my patent toincandescence, namely in from two to three seconds.

What is claimed is:

1. In a lighter for cigarettes and the like, an airtight casingconstituting an air pressure generator having a single opening to theoutside, an electric igniter resistor adjacent said opening, said casingbeing of operatively fixed volume, a holder for snugly holding acigarette in said opening adjacent said igniter resistor, an electricairheater resistor within said casing and connected in series with saidigniter resistor, characterized in that the air-heater resistorconstitutes a ballast resistor having a high temperature coefficient ofsuch value that its resistance at maximum operating temperature duringuse is at least several times its resistance when cold, whereby, whenthe electric circuit is first completed through said resistors, theinitially large electric current caused by the high temperaturecoetlicient ballast resistor flash-heats the igniter resistor andquickly heats the ballast resistor which generates a puff of fast movingair in timed sequence to light the cigarette.

2. A cigarette lighter according to claim 1 further characterized by thefact that the ballast resistor is in the form of a ribbon to facilitateheat transfer to the surrounding air and to minimize mass of theresistor.

3. A cigarette lighter according to claim 1 further characterized by thefact that said casing is multi-sectional and comprises a relativelysmall section and a relatively large section, said relatively smallsection being adapted to be mounted on the instrument panel of anautomobile and to support the igniter resistor, said relatively largesection being located remotely from the first 1,609,042

section and containing the ballast resistor, and a tube 560- 1,983,738

tion interconnecting said sections. 2,052,016

References Cited in the file of this patent 5 2,381,726

UNITED STATES PATENTS $605,380

1,362,227 Clark Dec. 14, 1920 are o Trapet Nov. 30, 1926 Davis Dec. 11,1934 Davis Aug. 25, 1936 Ashton et a1. Nov. 1, 1938 Davis Aug. 7, 1945Bauman et a1. July 29, 1952 Guernsey et a1. Ian. 17, 1956

